Iconic Mt. Fuji hasn’t erupted since 1707. But ever since last year’s giant earthquake and aftershocks, volcano-watchers have speculated that new tectonic pressures could be lighting the fuse.

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The latest warning comes from the National Research Institute for Earth Science and Disaster Prevention. Japanese press reported Thursday that researchers there concluded the March 11 quake and one aftershock four days later near Fuji put large pressure on the dormant volcano’s magma chamber, and that could trigger an eruption. The researchers said the pressure on the mountain now is bigger than 305 years ago, when Fuji last blew its top.

“It’s possible for Mt. Fuji to erupt even several years after the March 11 earthquake, therefore we need to be careful about the development,” a team researcher was quoted as saying.

That said…. as Kyodo News noted, pressure isn’t the only factor that could create an eruption — and no signs of an eruption have so far been detected.

In 2004, the government estimated a Fuji eruption would cost the economy ¥2.5 trillion ($31.25 billion) and would affect more than 400,000 people, including those in the Tokyo area. Researchers say volcanic dust from Mt. Fuji would travel more than 100 kilometers — the distance between the mountain and the city — and Tokyo’s capital functions could be lost for several months.

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